1. Field of the Invention
The present invention relates to a performance evaluation mechanism of a video watermarking algorithm, and more specifically, to a method and system for selecting test stimuli to insure a reliable evaluation result in evaluating performance of a video watermarking method.
2. Description of Related Art
Robustness is one of the important factors to consider in the evaluation of a video watermarking method. The robustness refers to a performance capable of detecting the existence of a watermark embedded in images even when distortion attacks are intentionally or unintentionally applied. In general, in order to evaluate the robustness of a video watermark algorithm, a specific watermark is embedded in a test stimuli, i.e., video data, with the associated watermarking algorithm, and then, various attack functions are applied to the stimuli in which the watermark has been embedded, in order to produce intentional distortion. Finally, by measuring the similarity between the detected watermark and the original watermark, the robustness of the watermark algorithm can be evaluated.
These kinds of robustness evaluation methods have been proposed in many scientific papers and utilized in real applications. However, although a lot of attack functions have been proposed and categorized, there has been no report or publication on the selection of the test stimuli in the evaluation process.
To insure reliable evaluation results for the robustness of each video watermarking method (or algorithm), it should be guaranteed that the evaluation process gives the same or very similar results for each test stimulus. However, it is impossible to achieve without establishing some criteria for the selection of the test stimuli. Therefore, in order to reliably evaluate the robustness of the video-watermarking algorithm, it is necessary to establish a standardized guideline for the selection of video stimuli.